/*
 * Copyright (C) 2012 Roman Yakovenko <erelus@gmail.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of
 * this software and associated documentation files (the "Software"), to deal in
 * the Software without restriction, including without limitation the rights to
 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
 * of the Software, and to permit persons to whom the Software is furnished to do
 * so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

package com.fuzzy.functions;

import com.fuzzy.core.Function;
import com.fuzzy.core.FuzzyPoint;

public class Generic implements Function {

    private FuzzyPoint[] points;

    public Generic(FuzzyPoint[] points) {
        this.points = points;
    }

    @Override
    public double getM(double value) {
        for (int i = 0; i < points.length - 1; i++) {
            if (value == points[i].getX()) {
                return points[i].getY();
            }

            if (value > points[i].getX() && value < points[i + 1].getX()) {
                double tanAlpha = Math.abs(points[i].getY() - points[i + 1].getY())
                        / Math.abs(points[i].getX() - points[i + 1].getX());
                return tanAlpha * (value - points[i].getX()) + Math.min(points[i].getY(), points[i + 1].getY());
            }

            if (value == points[i + 1].getX()) {
                return points[i + 1].getY();
            }
        }
        return Function.NOT_IN_SET;
    }

    @Override
    public FuzzyPoint[] toPoints() {
        return points;
    }
}
